Breakdown at BP Refinery Strains Midwest Gas Prices

A breakdown at a BP refinery outside Chicago is sending jolts across the energy markets of the Midwest and Canada, pushing up gasoline prices even as oil prices over all reached a six-year low.

Since a mechanical breakdown at BP’s refinery in Whiting, Ind., on Saturday, the wholesale price of gasoline has climbed 50 to 80 cents a gallon in a region that stretches from Great Lakes states like Michigan to as far south as parts of Kansas and Oklahoma.

In Illinois, the average price at the pump jumped on Thursday by 15 cents, to $2.78 a gallon for regular gasoline, according to AAA. In Michigan, regular gasoline jumped by even more, 23 cents a gallon to $2.81, AAA said, an almost unheard-of increase, except when hurricanes barrel through the refineries on the Gulf of Mexico.

Consumers around the area expressed confusion and frustration.

“If I had known this was going to happen, I could’ve filled up yesterday,” said Nancy Nester, a psychotherapist from West Bloomfield, Mich., as she fueled her car. “It makes me angry.” Ms. Nester’s Lexus calls for premium fuel, but she used regular instead to save money.

Drivers in almost all other parts of the country are paying considerably less than they were at the beginning of the summer as crude oil prices continue their sharp decline. On Thursday, the American benchmark for oil fell to $42 a barrel, a six-year low.

At the Whiting refinery, leaky pipes on a crude distillation unit built to process Canadian heavy crude forced BP to shut the unit, and experts say it could take as much as a month to fix the problem.

“It is a mess,” said Tom Kloza, global head of energy analysis at the Oil Price Information Service. “It might take a month to fix, and it’s a bad month to miss because you can still see a lot of summer driving.”

Refinery breakdowns are not unusual, but this one comes at a particularly bad time for Canadian oil producers. Because the Whiting plant is one of the primary processors of Canadian heavy crude in the United States, inventories are building north of the border.

The price of Western Canada Select, the benchmark for diluted bitumen from Alberta’s oil sands, sank to roughly $23 a barrel this week — about half the price of an American barrel of crude.

Canadian producers were already suffering from overproduction and a couple of pipeline breakdowns when the BP refinery experienced its problems. But the new breakdown is particularly damaging for Canadian producers and the Canadian economy, because the weeks leading up to Labor Day weekend have some of the heaviest demand of the year.

BP issued a short statement saying that it had shut down the largest of three distillation units at the plant “for unscheduled repair work.”

The company added: “BP is working to safely restart the unit as soon as possible. In the meantime, the company is working to meet its fuel supply obligations.”

The Whiting refinery is the largest in the Midwest and seventh largest in the country. It can refine as much as 270,000 barrels a day of diluted bitumen piped from Canada. The refinery has a total capacity to process 413,000 barrels of crude a day to produce 19 million gallons of fuel.

The problems at Whiting caps a summer of snags at various refineries in California, Missouri and other states that have led to sporadic higher regional prices, especially on the West Coast. Nevertheless, drivers on average have been paying a dollar less for a gallon of gasoline than they were last summer.

At the same time, refiners have been benefiting from the glut of cheap domestic oil and have been producing record amounts refined fuels. Refiners are making hefty profits, selling their reformulated gasoline on the spot market for $25, $50 and sometimes as much as $100 more per barrel than their cost of crude depending on the region.

“It has been a golden summer for refiners,” Mr. Kloza said.

But it is not a golden month for Michigan drivers.

“It seems like they keep coming up with all these mysterious reasons why the prices fluctuate,” said Jenny Osgood of suburban Southfield, Mich., “but who can really understand them?”

Mary M. Chapman contributed reporting.

A version of this article appears in print on , on Page B1 of the New York edition with the headline: Breakdown at BP Refinery Strains Midwest Gas Prices . Order Reprints | Today’s Paper | Subscribe